1. Field of the Invention
The present invention relates to a chain disconnecting and connecting tool for use for chains such as a roller chain for disconnecting the chain by pulling (removing) a pin out of the chain and connecting the chain by caulking (deforming) an end of a pin of a joint link (chain linking member) and more specifically to a chain disconnecting and connecting tool suitably applied to a motorcycle driving roller chain.
2. Related Art
Heretofore, the present applicants have proposed a chain disconnecting and connecting tool as disclosed in Japanese Patent No. 3431361 for example. This tool has first and second bodies whose right and left sides are opened in a direction of a longitudinal direction of a chain, that engage from each other in a vertical direction of the chain and that are coupled so as to be unable to relatively move in a direction of nipping the chain. The first body is provided with a pressure actuating member for pressing a pin or a plate of the chain and the second body is provided with a through hole through which the pin of the chain may penetrate and a slider having a pin abutting portion to which an end of the pin may abut.
The pin may be pulled out the chain and the chain may be disconnected by mounting the pin to be pulled out to the pressure actuating member and pressing the pressure actuating member toward the chain by means of screw engagement while adjusting the slider with the through hole. In contrast, the chain may be connected by caulking (deforming) an end of a pin of the chain by mounting the pin to be caulked (deformed) to the pressure actuating member and pressing the pressure actuating member toward the chain while adjusting the slider with the pin abutting portion.
Because the chain disconnecting and connecting tool described above has a center impeller structure with the first and second bodies, i.e., separate members, engaged in the vertical direction of the chain, the tool can fully sustain an operational load such as caulking (deformation) and may be downsized and lightened so as to be conveniently portable. Still more, the tool can nip a chain by separating the first and second bodies while attaching the chain to a motorcycle, so that workability could be improved.
However, because the chain disconnecting and connecting tool described above has had the center impeller structure in an operational state in which the first body is engaged with the second body, the operation is obliged to be carried out in a free span of the chain wound around between a driving sprocket wheel and a driven sprocket wheel. Therefore, there have been cases when the place to which the chain disconnecting and connecting tool is attached is limited, the operation becomes cumbersome or it becomes difficult to use the tool, depending on a shape of a swing arm of the motorcycle.
It is noted that although there also exists a chain disconnecting and connecting tool having a cantilever structure with a body block in a shape of C, this tool has had problems that in terms of durability, the body block is readily deformable due to the cantilever structure and that the tool would be large and heavy and be inconvenient to carry when a robust and highly rigid body block is used.
Accordingly, the present invention seeks to provide a chain disconnecting and connecting tool that solves the abovementioned problems by constructing the tool so that it may be used at a winding part of a sprocket of a chain and so as to receive an operational load at two places.